Pfizer, Moderna Looking At Adding A Third Vaccine Dose

(Undated) — Two drug companies are working on ways to better protect against COVID-19 variants. Moderna is testing a COVID-19 booster shot aimed at the South African strain. Meanwhile, Pfizer is conducting a clinical trial to see if a third dose of its vaccine will further boost antibody response to protect against variants of the virus. The company is also planning to test a modified version of its vaccine to see if it works against the South African variant. On Monday, the FDA released updated guidance which said modified coronavirus vaccines that protect against new, emerging variants may be authorized without the need for a long clinical study.